Electric gas or vapor lamp.



till

FRANZ SKAUPY,

PORATION 0F GERMANY.

OI BERLIN, GERMANY, ASSIGNOR AKTIENGESELLSCHAFT (AUERGESELLSCHAFT),

TO DEUTSCHE GASGL'fi'HLICHT OF BERLIN, GERMANY, A. COB- I ELECTRIC GAS, OR VAPOR LAMP.

l .dtl l ,20tl.

No Drawing.

1 To all whom it may concern consists therein, that such an electric gas or vapor lamp adapted to be operated by are light discharges contains, besides the gas or vapor made luminous by the passage of current, an inert gas or a mixture of gases not essentially taking part in the illuminating action and which is of such a high pressure that the arc is distinctly contracted either alone or after being mixed together with the luminous vapor or gas.

its inert gas, for instance a rare gas of the atmosphere may be used. Pure argon as inert gas has given the most satisfactory results on account of its excellent conductivity and its comparatively low price. As luminous substances the vapors of easily volatile metals, or of metalloids and their compounds especially the halogen-compounds may be used. These vapors may be produced by the vaporization of the cathode or they may enter the path of the current from any other place, for instance from the anode.

The high ressure of the inert gas is chosen in con ormity with the luminous substance. Tn lamps using mercury as illuminating vapor a substantial contraction of the arc is obtained by using a pressure of higher value, for instance of 100 mm. argon, while in the case of employing saltvapors as luminous substance, of zirconium, a pressure of about 3 mm. argon is already sufficient.

The lamps constructed according to my invention present, compared with the hitherto known lamps, many advantages. high gas-pressure existing in the lamp produces a comparatively high potential fall taking place substantially at the moment of lighting the lamp. There results a high watt-load of the lamp per unit of length, even with currents of medium intensity,

which facilitates the rapid vaporization of for instance the chlorid The Specification of Letters Patent. Patented Jan, 14, 1919.

Application filed June 9, 1916. Serial No. 102,768.

the substance serving to produce the luminous action. A further advantage is gained in that the arc passes from the anode to the cathode in the shape of a column, having a. narrow cross-section, without touching the walls of the tube, so that consequently the walls of the tube remain comparatively cold contrary to the known mercury-high-voltage lamps in which the high pressure can only be maintained by high temperatures of the walls of the tube. This fact. permits the use of glass whereas with the above-mentioned mercury-lamps only quartz may be employed. As the path of current is en tirely clear of the walls of the tube, the walls are not at all or not appreciable chemically attacked by the particles of vapor. This is of the highest importance especially in the case of lamps containing vapors of the alkali-metals, because the vapors of these lamps develop even at a low concentration a considerable luminous power with the high temperature'of the high-pressure arc.

Tf mercury vapor is employed as luminous substance in a lamp according to my invention, the troublesome high intensity of current taking place in the known systems of high-pressure mercury lamps during the burning-in period is dispensed with. There is a further advantage that a low partial mercury pressure exists in the gas mantle surrounding the arc, while in the usual highpressure mercury lamps just the most ellicacious fraction of the ultraviolet radiation, namely the line 2536 u u. is absorbed and made inoperative by the concentrated vapor inclosing the arc.

The lighting of the lamps is effected in the well known manner, for instance by producing a high-voltage impulse by means of a vacuum-interrupter and a self-induction.

What it claim as my invention and desire to secure by Letters Patent is 1. A lamp of the class described compris-Q ing a receptacle which contains both a substance adapted to conduct the current and to be made luminous thereby and a substantially inert gas which does not appreciably share in the production of luminous effects, said inert gas being at such high pressure that the light column is contracted in cross section and spaced away from the walls of the receptacle.

- 2. A lamp of the class described COIl'lPIiS- to be made luminous thereby and argon at ing a receptacle whlch contains both a subsuch high pressure that the light column is stance adapted to conduct the current and to contracted 1n cross section and spaced away be made luminous thereby and a rare gas of from the walls of the receptacle. 15 the atmosphere at relatively high pressure In testlmony whereof, I have hereunto set said rare gas not being adapted to share apmy hand. preclably 1n the productlon of lumlnous ff t FRANZ SKAUPY.

.i i v Witnesses: 6. A lamp of the class descnbed comprlsing a receptacle which contains both a sub- HENRY HASPER,

stance adapted to conduct the current and ALLEN F. JENNINGS. 

